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Novel liquid chromatography method based on linear weighted regression for the fast determination of isoprostane isomers in plasma samples using sensitive tandem mass spectrometry detection
PublicationA simple, fast, sensitive and accurate methodology based on a LLE followed by liquid chromatography–tandem mass spectrometry for simultaneous determination of four regioisomers (8-iso prostaglandin F2α, 8-iso-15(R)-prostaglandin F2α, 11β-prostaglandin F2α, 15(R)-prostaglandin F2α) in routine analysis of human plasma samples was developed. Isoprostanes are stable products of arachidonic acid peroxidation and are regarded as the...
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Local dynamics of fluids and dielectrics as the foundation of signal-carrying wave properties
PublicationThis paper develops an original approach to fundamental problems of classical linear acoustics and electromagnetics, proving a crucial role of doubly-dynamic local properties of a propagation medium in supporting wave-like fields able to carry information signals. The proof is composed of two steps concerning, subsequently, fluid acoustics and dielectric electromagnetics. The first step consists in complementing a common, practically...
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Computationally Efficient Multi-Objective Optimization of and Experimental Validation of Yagi-Uda Antenna
PublicationIn this paper, computationally efficient multi-objective optimization of antenna structures is discussed. As a design case, we consider a multi-parameter planar Yagi-Uda antenna structure, featuring a driven element, three directors, and a feeding structure. Direct optimization of the high-fidelity electromagnetic (EM) antenna model is prohibitive in computational terms. Instead, our design methodology exploits response surface...
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An asymmetrical λ-foot of condensing steam flow in the IMP PAN nozzle
PublicationIn the present paper we have focused on the precise prediction of the spontaneous condensation phenomena in wet steam flow. Novelty of our approach lies on modelling both the moment of initiation of a phase transition, as well as the moment of its reverse progress - called here re-vaporization of the condensate phase. The practical issue is to elaborate of a model of spontaneous condensation/vaporization of water steam flow...
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Emergent approach to Knowledge Management by Small Companies: multiple case-study research
PublicationPurpose: The aim of this paper is to examine knowledge management approach followed by small companies on the example of firms from the knowledge-intensive business services (KIBS) sector. Design/methodology/approach: The study is based on the results of a qualitative survey involving 12 owners and managers of small companies operating in the KIBS sector. The survey uses the case study method. Findings: The findings confirm that...
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Comparison of strain results at a laser weld notch obtained by numerical calculations and experimental measurements
PublicationIn the development of ship structures applying new materials and it’s purposeful placement play an important role. During the last years, especially in a construction of ro-ro type vessels, the usage of novel sandwich structures in cargo decks is profitable. Steel sandwich panel is an innovative solution which at a todays state of development can be used for the construction of any members not taking part in a global bending of...
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Nonlinearity shaping in nanostructured glass-diamond hybrid materials for optical fiber preforms
PublicationNanodiamond integration with optical fibers has proved a compelling methodology for magneto-optics. We reveal that the applicability of nanodiamonds in nonlinear optics goes beyond the previous demonstrations of frequency converters. Instead, we exploit the recently reported volumetric integration of nanodiamonds along the optical fiber core and show that the nonlinear response of glasses can be manipulated by nanodiamonds. By...
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Quiet Quitting and its Link With Knowledge Risks in Organizations – Theoretical Insights
PublicationPurpose: Quiet quitting has become a widely publicized concept, driven by social media in the United States and other countries in 2022. It is a term used to describe the phenomenon by which employees do the least amount of their work, just enough to meet the requirements of one’s job description (Mahand and Caldwell, 2023). The trend is spreading quickly among young workers. It can potentially harm individuals, job performance,...
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Improving the prediction of biochar production from various biomass sources through the implementation of eXplainable machine learning approaches
PublicationExamining the game-changing possibilities of explainable machine learning techniques, this study explores the fast-growing area of biochar production prediction. The paper demonstrates how recent advances in sensitivity analysis methodology, optimization of training hyperparameters, and state-of-the-art ensemble techniques have greatly simplified and enhanced the forecasting of biochar output and composition from various biomass...
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Cost-Efficient Multi-Objective Design of Miniaturized Microwave Circuits Using Machine Learning and Artificial Neural Network
PublicationDesigning microwave components involves managing multiple objectives such as center frequencies, impedance matching, and size reduction for miniaturized structures. Traditional multi-objective optimization (MO) approaches heavily rely on computationally expensive population-based methods, especially when exe-cuted with full-wave electromagnetic (EM) analysis to guarantee reliability. This paper introduces a novel and cost-effective...
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Infographics in Educational Settings: A Literature Review
PublicationInfographics are visual representations of data that utilize various graphic elements, including pie charts, bar graphs, line graphs, and histograms. Educators and designers can maximize the potential of infographics as powerful educational tools by carefully addressing challenges and capitalizing on emerging technologies. However, current education systems showcase the need for development guidelines and the best practices targeted...
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Energy-Efficient Self-Supervised Technique to Identify Abnormal User Over 5G Network for E-Commerce
PublicationWithin the realm of e-commerce networks, it is frequently observed that certain users exhibit behavior patterns that differ substantially from the normative behaviors exhibited by the majority of users. The identification of these atypical individuals and the understanding of their behavioral patterns are of significant practical significance in maintaining order on e-commerce platforms. One such method for accomplishing this objective...
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The Most Valuable Global Brands and Condition of Economies: a Spatial Approach
PublicationResearch background: Brands are considered to be the most valuable asset of a company. Some of them achieve spectacular global results. The significance of global brands is proved by the fact that their value is often greater than the sum of all company’s net assets. Purpose of the article: The aim of this article is to highlight that brand value does not only create company’s value but also leverages economies. We claim that even though...
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Collective creativity in management science
PublicationPurpose: The purpose of this paper is to establish the current state of knowledge on collective creativity in management science on the basis of a systematic literature review. Methodology: A systematic review was performed based on the three-step SPL procedure proposed by Tranfield et al. (2003). Two databases (Scopus and Web of Science) were searched electronically up until March 2022. Based on the secondary data a literature...
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Politics and urban artifacts in cities: what are they and how are they interconected?
PublicationThis research, analyses the effect of politics on a city and its image, via their control over the formation or changes on urban artifacts. It analyses the concepts introduced in Aldo Rossi’s architectural monograph, The Architecture of the City, in the chapter titled ‘Politics as Choice’, and his idea that a city’s image is a reflection of its political institutions and the choices people in authority make. Monuments and architecture...
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Quality assessment of low voltage surge arresters
PublicationUsers expect reliable operation of the surge arrester during overvoltages, which may originate from a switching process or a lightning discharge. The necessary conditions to guarantee these expectations are: appropriate construction of the surge arrester, its production being maintained in accordance with technical standards, and a positive results of the type test (as well routine and acceptance tests). The recipient, especially...
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Rapid multi-criterial design of microwave components with robustness analysis by means of knowledge-based surrogates
PublicationManufacturing tolerances and uncertainties concerning material parameters, e.g., operating conditions or substrate permittivity are detrimental to characteristics of microwave components. The knowledge of relations between acceptable parameter deviations (not leading to violation of design specifications) and the nominal performance (not considering uncertainties), and is therefore indispensable. This paper proposes a multi-objective...
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Effect of Tool Positioning Factors on the Strength of Dissimilar Friction Stir Welded Joints of AA7075-T6 and AA6061-T6
PublicationFriction Stir Welding (FSW) is a solid-state bonding technique. There are many direct and indirect factors affecting the mechanical and microstructural properties of the FSW joints. Tool offset, tilt angle, and plunge depth are determinative tool positioning in the FSW process. Investigating the effect of these factors simultaneously with other parameters such as process speeds (rotational speed and translational speed) and tool...
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Digital transformation and economic growth - DESI improvement and implementation
PublicationThe paper aims to improve the methodology of the Digital Economic and Society Index (DESI), the European Commission’s newest index to assess the development of the digital economy. In particular, we investigate whether methodological changes to the structure of DESI improve its ability to capture the digital transformation of EU economies. Using the sensitivity- based analysis, we check whether the selection of weights of individual...
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Fast EM-Driven Parameter Tuning of Microwave Circuits with Sparse Sensitivity Updates via Principal Directions
PublicationNumerical optimization has become more important than ever in the design of microwave components and systems, primarily as a consequence of increasing performance demands and growing complexity of the circuits. As the parameter tuning is more and more often executed using full-wave electromagnetic (EM) models, the CPU cost of the overall process tends to be excessive even for local optimization. Some ways of alleviating these issues...
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Exploring the relationship between investment choices, cognitive abilities risk attitudes and financial literacy
PublicationPurpose The main purpose of this study is to investigate the investment choices' relationship with cognitive abilities, risk aversion, risky investment intentions, subjective financial literacy and objective financial literacy. Design/methodology/approach To examine the relationship, two investment choices were given to 256 subjects from Pakistan. Questionnaire had total 20 questions for measuring five variables. To review this...
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Comprehensive analysis of low-temperature methods for reclaiming of ground tire rubber
PublicationManagement of waste tires has become an important topic for decades. The lack of an effective method to manage the materials as mentioned above leads to illegal landfills. This problematic waste can be divided into two main categories depending on the physical condition of the waste: (i) partially used tires; (ii) end-of-life tires. While the first group can be reused or retreaded, the second group requires special measures to...
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THE PROTECTIVE MEASURES AGAINST SARS-COV-2 INFECTION IN THE SEAFOOD COMPANY FROM THE PERSPECTIVE OF THE EMPLOYEES
PublicationPurpose: To identify and discuss the protective measures implemented to prevent SARS-CoV-2 infection among employees. Design/methodology/approach: The four-stage course of research. Case study and structured interviews with all employees, directly and indirectly, involved in food processing. Research questions: (R1) What measures have been taken to prevent the risk of infection among employees? (R2) What activities and responsibilities...
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Reasons behind changes in the share of labour in national income in the Polish economy: Selected aspects
PublicationAim/purpose – The aim of this paper is to examine the impact of structural changes taking place in the Polish economy on the share of labour in national income. Design/methodology/approach – The scope of this study includes a review of the literature dedicated to the issue and an empirical analysis of data available on this topic. The study uses elements of descriptive statistics and the method of induction. Findings – The conducted...
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Torque capacity of multidisc wet clutch with reference to friction occurrence on its spline connections
PublicationIn this article developed mathematical model that includes friction occurrence on spline connections is presented. The work also contains results of experimental research on torque capacity of multidisc wet clutch. These results are expressed as a function of contact pressure for different number of friction surfaces. Due to increased interest in research concerning multidisc wet clutches it is essential to determine impact of...
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Influence of addition of carbon nanotubes on rheological properties of selected liquid lubricants - a computer simulation study
PublicationThis work is motivated by the improvement of anti-friction properties of lubricants by addition of CNTs proved experimentally in literature. In particular, a methodology is developed to compute the shear viscosity of liquid lubricants (Propylene Glycol) based on Molecular Dynamics simulation. Non-Equilibrium molecular dynamics (NEMD) approach is used with a reactive force field ReaxFF implemented in LAMMPS. The simulations are...
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Globalized parametric optimization of microwave components by means of response features and inverse metamodels
PublicationSimulation-based optimization of geometry parameters is an inherent and important stage of microwave design process. To ensure reliability, the optimization process is normally carried out using full-wave electromagnetic (EM) simulation tools, which entails significant computational overhead. This becomes a serious bottleneck especially if global search is required (e.g., design of miniaturized structures, dimension scaling over...
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Analysis of GNSS, Hydroacoustic and Optoelectronic Data Integration Methods Used in Hydrography
PublicationThe integration of geospatial data in hydrography, performed using different measurement systems, involves combining several study results to provide a comprehensive analysis. Each of the hydroacoustic and optoelectronic systems is characterised by a different spatial reference system and the method for technical implementation of the measurement. Therefore, the integration of hydrographic data requires that problems in selected...
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Design specification management with automated decision-making for reliable optimization of miniaturized microwave components
PublicationThe employment of numerical optimization techniques for parameter tuning of microwave components has nowadays become a commonplace. In pursuit of reliability, it is most often carried out at the level of full-wave electromagnetic (EM) simulation models, incurring considerable computational expenses. In the case of miniaturized microstrip circuits, densely arranged layouts with strong cross-coupling effects make EM-driven tuning...
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Mapping of Flood-Prone Areas Utilizing GIS Techniques and Remote Sensing: A Case Study of Duhok, Kurdistan Region of Iraq
PublicationOne of the most common types of natural disaster, floods can happen anywhere on Earth, except in the polar regions. The severity of the damage caused by flooding can be reduced by putting proper management and protocols into place. Using remote sensing and a geospatial methodology, this study attempts to identify flood-vulnerable areas of the central district of Duhok, Iraq. The analytical hierarchy process (AHP) technique was...
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Security of Cryptocurrencies: A View on the State-of-the-Art Research and Current Developments
Publication[Context] The goal of security is to protect digital assets, devices, and services from being disrupted, exploited or stolen by unauthorized users. It is also about having reliable information available at the right time. [Motivation] Since the inception in 2009 of the first cryptocurrency, few studies have been undertaken to analyze and review the state-of-the-art research and current developments with respect to the security...
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Ocena klimatu akustycznego w przestrzeni pasażerskiej elektrycznego zespołu trakcyjnego serii EN57
PublicationW pracy przedstawiono wyniki badań poziomów dźwięku w przestrzeni pasażerskiej elektrycznego zespołu trakcyjnego (EZT) serii EN57 podczas postoju, rozruchu, jazdy oraz hamowania. Badania przeprowadzono na podstawie autorskiej metodyki badawczej bazując na normie PNEN ISO 3381:Kolejnictwo. Akustyka. Pomiar hałasu wewnątrz pojazdów szynowych. Badania przeprowadzono na linii kolejowej nr 250 od przystanku Gdańsk Śródmieście do stacji...
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Długie pociągi
PublicationWskazano, że przy wprowadzaniu długich pociągów pojawiają się możliwości, ale i ograniczenia różnej natury oraz problemy do rozwiązania. Inne w przypadku długich pociągów i inne w przypadku ciężkich pociągów. Pokazano długie pociągi, jako szansę na polepszenie bezpieczeństwa na drogach, poprzez ograniczenie na nich ruchu samochodów ciężarowych. Łatwiej będzie w praktyce realizować pomysł „Tiry na tory” Długie pociągi są szansą...
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Koncepcja międzynarodowej konkurencyjności makrootoczenia przedsiębiorstw
PublicationCelem badań przedstawionych w niniejszym artykule jest opracowanie koncepcji konkurencyjności międzynarodowej (IC) krajów, której podstawą jest makroekonomiczne otoczenie przedsiębiorstw. Motywem podjęcia tych badań były poważne wady metodologii pomiaru IC gospodarek stosowanej przez Światowe Forum Ekonomiczne (WEF). WEF rekomenduje Globalny Indeks Konkurencyjności (GCI) jako globalną miarę produktywności kraju. WEF utrzymuje,...
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Indeksy demokracji i stan zaawansowania ich rozwoju ze szczególnym uwzględnieniem projektu Varieties of Democracy - Democracy indices and their state of development with a special focus on the Varieties of Democracy project
PublicationIndeksy demokracji już od wielu lat pomagają naukowcom w klasyfikowaniu reżimów politycznych na całym świecie. Czy jednak projekty tego typu mierzyły i mierzą jakość demokracji w sposób adekwatny? Na podstawie przeglądu literatury przedmiotu można stwierdzić znaczny rozwój metodologii w tym zakresie od końca XX wieku w odpowiedzi na wcześniejsze braki.Autor artykułu opisuje rozwój indeksów demokracji od pierwszych...
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Prognozowanie właściwości złączy spawanych pod wodą metodą lokalnej komory suchej
PublicationNiniejsza praca jest poświęcona spawaniu pod wodą metodą lokalnej komory suchej (MLKS) i przedstawia metodologię oraz narzędzia umożliwiające prognozowanie właściwości złączy spawanych wykonanych przy zastosowaniu tej odmiany spawania. Monografia zawiera opis rozwoju spawania pod wodą oraz charakterystykę metod wykorzystywanych do realizacji prac spawalniczych. Zaproponowano nowy podział metod spawania pod wodą, uwzględniający...
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Accelerated design optimization of miniaturized microwave passives by design reusing and Kriging interpolation surrogates
PublicationElectromagnetic (EM) analysis has become ubiquitous in the design of microwave components and systems. One of the reasons is the increasing topological complexity of the circuits. Their reliable evaluation—at least at the design closure stage—can no longer be carried out using analytical or equivalent network representations. This is especially pertinent to miniaturized structures, where considerable EM cross-coupling effects occurring...
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Accelerated multi-objective design of miniaturized microwave components by means of nested kriging surrogates
PublicationDesign of microwave components is an inherently multiobjective task. Often, the objectives are at least partially conflicting and the designer has to work out a suitable compromise. In practice, generating the best possible trade‐off designs requires multiobjective optimization, which is a computationally demanding task. If the structure of interest is evaluated through full‐wave electromagnetic (EM) analysis, the employment of...
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Modelling and simulation of GPU processing in the MERPSYS environment
PublicationIn this work, we evaluate an analytical GPU performance model based on Little's law, that expresses the kernel execution time in terms of latency bound, throughput bound, and achieved occupancy. We then combine it with the results of several research papers, introduce equations for data transfer time estimation, and finally incorporate it into the MERPSYS framework, which is a general-purpose simulator for parallel and distributed...
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Solvent dependency of carbon dioxide Henry's constant in aqueous solutions of choline chloride-ethylene glycol based deep eutectic solvent
PublicationThe Henry's constants of carbon dioxide absorbed in aqueous solutions of ethaline (choline chloride-ethylene glycol) were determined for temperatures ranging from 303.15 to 323.15 K based on solubility measurement at CO2 pressure ranging from 0 to 6 bar (0.6 MPa). These studies revealed that the Henry's constant increased with the increase of temperature. Data indicated the highest capacity of CO2 absorption is obtained for ethaline...
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Effect of the Drying Method of Pine and Beech Wood on Fracture Toughness and Shear Yield Stress
PublicationThe modern wood converting processes consists of several stages and material drying belongs to the most influencing future performances of products. The procedure of drying wood is usually realized between subsequent sawing operations, affecting significantly cutting conditions and general properties of material. An alternative methodology for determination of mechanical properties (fracture toughness and shear yield stress) based...
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Updating the Coupling Algorithm between HYDRUS and MODFLOW in the HYDRUS Package for MODFLOW
PublicationThe HYDRUS-based flow package for MODFLOW (the HPM or the HYDRUS package) is an existing unsaturated zone flow package for MODFLOW. In MODFLOW with the HPM, the groundwater modeling domain is discretized into regular grids that can be combined into multiple zones based on similarities in soil hydrology, topographical characteristics, and the depth to the groundwater. Each of these zones is assigned one unsaturated soil profile...
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A rapid dispersive liquid–liquid microextraction of antimicrobial onion organosulfur compounds in animal feed coupled to gas chromatography-mass spectrometry
PublicationA rapid analytical procedure is proposed for determining two antimicrobial onion organosulfur compounds, propyl disulfide (PDS) and propyl propane thiosulfonate (PTSO), in animal feed. The use of PTSO as a natural ingredient in animal feed is allowed due to its antimicrobial activity against pathogenic organisms. Two analytical methodologies using gas chromatography coupled to mass spectrometry (GC-MS) are compared. After the extraction...
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Towards bees detection on images: study of different color models for neural networks
PublicationThis paper presents an approach to bee detection in videostreams using a neural network classifier. We describe the motivationfor our research and the methodology of data acquisition. The maincontribution to this work is a comparison of different color models usedas an input format for a feedforward convolutional architecture appliedto bee detection. The detection process has is based on a neural...
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Optimization-based antenna miniaturization using adaptively-adjusted penalty factors
PublicationThe continuing trend for miniaturization of electronic devices necessitates size reduction of the comprising components and circuitry. Specifically, integrated circuit-antenna modules therein require compact radiators in applications such as 5G communications, implantable and on-body devices, or internet of things (IoT). The conflict between the demands for compact size and elec-trical and field performance can be mitigated by...
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Explicit Size-Reduction of Circularly Polarized Antennas through Constrained Optimization with Penalty Factor Adjustment
PublicationModern communication systems of high data capacity incorporate circular polarization (CP) as the preferred antenna radiation field configuration. In many applications, integration of the system circuitry with antennas imposes size limitations on CP radiators, which makes their development process a challenging endeavor. This can be mitigated by means of simulation-driven design, specifically, constrained numerical optimization....
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Inflation Forecast or Forecast(s) Targeting?
PublicationThe paper refers to L.E.O. Svensson’s concept of inflation forecast targeting (IFT) and its implementation by central banks of Sweden, Norway and the Czech Republic. The study focuses on (1) inflation forecasts published by selected central banks, i.e.headline inflation and core or monetary policy-relevant (MPR) inflation, which are made on the assumption of endogenous instrument rate, (2) one-year consumer...
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Experimental and analytical thermal study of PTFE composite sliding against high carbon steel as a function of the surface roughness, sliding velocity and applied load
PublicationThis study investigates the contact temperatures caused by frictional heating of sliding parallel pairs. In this case the materials studied are a PTFE composite in contact with a high carbon steel plate. These materials are commonly used for industrial applications, in particular as the main contacting components within a scroll expander system. The expected contact temperature values are important to be quantified in order to...
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Antecedents and outcomes of social media fatigue
PublicationPurpose – This study aims to explore which of four chosen factors (i.e. privacy concerns, FoMO, self-disclosure and time cost) induce a feeling of strain among Facebook users in terms of social media fatigue (SMF), and if this occurs, whether it further influences such outcomes as discontinuance of usage (DoU) and interaction engagement decrement (IED). Design/methodology/approach – Through an online structured questionnaire, empirical...
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Urban flash flood hazard identification and assessment applying geospatial techniques and hydrodynamic modeling; Erbil city case study, Kurdistan Region of Iraq
PublicationThis dissertation aims to investigate the factors behind flash flooding in Erbil's central district, located in the Kurdistan Region of Iraq, and develop a methodology for assessing flood hazards in the city, despite limited data accessibility. In this thesis, each factor was investigated, including analyzing extreme precipitation events in the last two decades, including their spatial and temporal distribution of rainfall, intensity,...